1. Technical Field
This invention relates generally to the field of printing devices. More specifically, this invention relates to printing colored images using International Color Consortium (ICC) color management.
2. Description of the Related Art
Presently, for printing colored images using International Color Consortium (ICC) color management, there are three methods of color rendering or rendering intents available in the art. Such three methods are referred to by one skilled in the art as perceptual rendering intent (Perceptual RI), colorimetric rendering intent (Colorimetric RI), and saturation rendering intent (Saturation RI.) Each such rendering intent uses pre-calculated color lookup tables (CLUT), e.g. A2B and B2A tables, which are embedded in the ICC color profile describing the particular output device. CLUT may be stored as an n-dimensional array, where each dimension has a number of entries in accordance with the number of grid points (see Specification ICC.1:2004-10.) Examples of output devices discussed herein may include, but are not limited to, inkjet printers, laser printers, photographic imaging devices, and printing presses.
For purposes of discussion herein, applying Perceptual RI or Saturation RI may be viewed by one skilled in the art as squeezing or compressing an entire color space or gamut from the device of the source image, such as a scanning device or camera, into the available gamut of the output device, such as a digital printer. Such action has the effect of changing or altering all the colors that are to be rendered, i.e. inside and outside of the gamut of the output device.
For purposes of discussion herein, applying Colorimetric RI may be viewed as keeping colors that are inside the gamut of the printing device as they are while clipping out-of-gamut colors to the nearest available color.